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R. P. Hallett K. G. McKay S. P. Balm A. W. Allaf H. W. Kroto A. J. Stace 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1995,34(1):65-70
Reaction studies of carbon clustersC
n
in the rangen=8–37, produced by laser vaporisation in a supersonic nozzle, have been investigated using time-of-flight mass spectrometry. Clear differences in reaction products formed on hydrogenation are detected which show that even and odd clusters behave quite differently and furthermore thatat least two different types of even cluster appear to exist. The reactivity patterns for clusters C
n
withn=16, 18 and 22 are in a different class from those withn=20, 24, 26 ..., a behaviour consistent with the existence of closed cage fullerene structures for even clusters with 20 or more carbon atoms (other thann=22). 相似文献
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J. C.T.R. Burckett St. Laurent P. B. Hitchcock M. A. King H. W. Kroto M. F. Meidine S. I. Klein 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):259-262
Abstract The chemistry of the novel phospha-alkenes RP[dbnd]CR'2, and phospha-alkynes, RC[tbnd]P, containing 2pπ-3pπ bonds is of current interest.1,2 Recent molecular orbital calculations,3,4 suggest that the highest occupied molecular orbital in CH2[dbnd]PH is of the π-type with the phosphorus lone pair ó-orbital only slightly more stable while the π? lumo orbital is relatively low lying. We now report He (I) photoelectron spectroscopic studies on a variety of RC[tbnd]P molecules5,6 which indicate that the homo is also of the π-type and the π-σ separation is much greater than that found in the analogous RC[tbnd]N systems. 相似文献
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A detailed rotational analysis of the microwave spectrum between 26.5 and 40 GHz of phosphaethene, CH2PH, has been carried out. This molecule is the simplest member of a new class of unstable molecules—the phosphaalkenes. The species can be produced by pyrolysis of (CH3)2PH, CH3PH2 and also somewhat more efficiently from Si(CH3)3CH2PH2. Full first-order centrifugal distortion analyses have been carried out for both 12CH231PH and 12CH231PD yielding: A0 = 138 503.20(21), B0 = 16 418.105(26), and C0 = 14 649.084(28) MHz for 12CH231PH. The 101-000μA lines have also been detected for 13CH2PH, cis-CDHPH and trans-CHDPH. These data have enabled an accurate structure determination to be carried out which indicates: . The dipole moment components have been determined as μA = 0.731 (2), μB = 0.470 (3), μ = 0.869 (3) D for CH2PH; μA = 0.710 (2), μB = 0.509 (10), μ = 0.874 (7) D for CH2PD. 相似文献
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The new molecule 1-phosphabut-3-ene-1-yne, CH2=CHCP, produced by pyrolyzing prop-1-ene-3-phosphorus dichloride, CH2=CHCH2PCl2, was detected by microwave spectroscopy. The analysis of the rotational transitions indicates that the molecule is planar with constants: A0 = 46 694(24), B0 = 2807.7100(21), and C0 = 2645.8356(21) MHz. These rotational constants indicate that the structure of the vinyl group is essentially the same as that in CH2=CHCN and CH2=CHCCH; r(C---C) = 1.432 Å and (C=C---C) = 123.9°. The dipole moment parameters are μA = 1.181(2), μB = 0.074(1), and μ = 1.183(2) D. The vibrational satellite spectra for the C---CP bending modes indicate that ν11(a′) = 184 ± 30 cm−1 and ν15(a″) = 263 ± 30 cm−1. 相似文献
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The rotational spectrum of the unstable molecule selenoacetaldehyde, CH3CHSe, has been studied by microwave spectroscopy between 26.5 and 40 GHz. Transitions have been measured for five abundant selenium isotopic variants. These measurements have, together with structural information from the related molecules CH3CHS and CH3CHO, allowed reliable data on the C=Se bond length (1.758 ± 0.01 Å) and the
e angle (125.7 ± 0.3°) to be derived. The spectral lines show splittings due to hindered internal rotation and using these together with the derived structure, barrier heights of 1602 cal mole−1 (6703 J mole−1) and 1648 cal mole−1 (6859 J mole−1) have been determined for the ground and first torsionally excited states, respectively. 相似文献